EP 0775918 A3 20000628 - Transmission-reception system
Title (en)
Transmission-reception system
Title (de)
Sende- und Empfangssystem
Title (fr)
Système de transmission et réception
Publication
Application
Priority
JP 30413395 A 19951122
Abstract (en)
[origin: EP0775918A2] The invention relates to a transmission-reception system. A transponder receiver unit contained in the key bow of an ignition key has a power circuit that receivers, rectifies and smoothes the carrier wave signal transmitted together with a time reference signal and an enquiry signal from the transmission-reception ECU of a motor vehicle. A microcomputer in the transponder becomes active when the output voltage of the power circuit reaches a predetermined level or higher. When activated, the microcomputer measures the time length of the received reference time signal using the clock signal generated by an oscillation circuit, and calculates a ratio, as a correction coefficient, between the measured time length and a stored reference time value. The microcomputer decodes the enquiry signal while correcting the time information included in the time series pulse signal forming the enquiry signal, using the correction coefficient. <IMAGE>
IPC 1-7
IPC 8 full level
B60R 25/04 (2013.01); B60R 25/24 (2013.01); F02N 15/00 (2006.01); G01S 13/75 (2006.01); G07C 9/00 (2006.01); H04B 1/59 (2006.01); H04B 5/48 (2024.01); H04B 7/26 (2006.01); H04L 9/32 (2006.01); H04Q 9/00 (2006.01); H04Q 9/14 (2006.01); H04W 4/04 (2009.01); H04W 12/02 (2009.01)
CPC (source: EP KR US)
B60R 25/04 (2013.01 - EP US); G01S 13/758 (2013.01 - EP US); G07C 9/00309 (2013.01 - EP US); H04B 1/40 (2013.01 - KR); G07C 2009/00777 (2013.01 - EP US)
Citation (search report)
- [A] US 5376932 A 19941227 - SAMOKINE GEORGES [FR], et al
- [A] GB 2257552 A 19930113 - TRW SIPEA SPA [IT]
- [A] EP 0532989 A1 19930324 - SIEMENS AG [DE], et al
- [A] EP 0311112 A2 19890412 - MATSUSHIMA KOGYO KK [JP]
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
EP 0775918 A2 19970528; EP 0775918 A3 20000628; JP H09142257 A 19970603; KR 100387140 B1 20030819; KR 970031411 A 19970626; US 5838254 A 19981117
DOCDB simple family (application)
EP 96118717 A 19961121; JP 30413395 A 19951122; KR 19960051502 A 19961101; US 75479996 A 19961121